1. Field of the Invention
The invention relates generally to devices which record information on a magnetic medium. More particularly, the invention concerns an improvement which increases the data rate of such devices.
2. Description of the Prior Art
Magnetic recording devices are used to write information to a magnetic medium either in analog or digital form. The magnetic medium is typically a tape, such as used in the well-known compact cassette, or known high density drives for computers which are used for backup purposes. Another common form is a disk, such as a floppy disk or a hard disk for storing programs and data in a computer.
The write channel for a magnetic recording device includes a thin film inductive head (referred to herein as "within film head", "TFH", or simply "inductive head") in close proximity with the magnetic medium. A write amplifier drives a current through the head to generate a flux which very locally alters the orientation of the magnetic material, thereby writing information on the magnetic medium. The write amplifier is coupled to circuitry which receives the information to be recorded and processes the information in a form suitable for the write amplifier and according to a selected data format.
When information is written in digital form, such as for computer data storage or digital recording of music, a current is driven through the inductive head in one direction to write a binary "0" and in the opposite direction to write a "1". When the medium is read by a suitable head, such as a magneto-resistive head, the portions recorded with a binary "0" will induce a current in the head in the one direction and portions recorded with a binary "1" will induce a current in the opposite direction, which is then decoded.
The continuing goal of those in the art is to increase the recording densities and speed (data rate) of recording to a magnetic medium. Improving the recording density allows more information to be written in a given space of the medium. Improving the recording speed is important for allowing the huge amounts of information required by today's multimedia applications to be recorded in time periods acceptable to the user. Data rates on the order of 500-600 Mb/s are proposed for near term hard disk drives for computers.